Magnetism and Matter
1.0 Introduction
1.0 Introduction
The property of any object by virtue of which it can attract a piece of iron or steel is called magnetism.
Natural Magnet
A natural magnet is an ore of iron $(Fe_3O_4),$ which attracts small pieces of iron, cobalt and nickel towards it.
Magnetite or lode stone is a natural magnet.
Artificial Magnet
A magnet which is prepared artificially is called an artificial magnet, e.g., a bar magnet, an electromagnet, a magnetic needle, a horse-shoe magnet etc. According to molecular theory, every molecular of magnetic substance (whether magnetised or not) is a complete magnet itself. The poles of a magnet are the two points near but within the ends of the magnet, at which the entire magnetism can be assumed to be concentrated. The poles always occur in pairs and they are of equal strength. Like poles repel and unlike poles attract.
